1. Field of the Invention
The present invention relates generally to devices for heating plastic pipe for the purpose of bending the pipe and, more particularly, to portable devices for heating plastic pipe so that it can be bent to a desired angle.
2. Discussion of the Background Art
Contractors who work with plastic pipe often use a pipe heating device to bend pvc pipe in order to form a difficult angle which would otherwise require multiple fittings and cuts. An example of such a pipe heater is a Greenlee Textron's "Hot Box" which utilizes a resistance style heating element but which has the disadvantage of requiring a high degree of diligence on the part of the operator in that the pipe must be turned or rotated often to avoid overheating and or burning a portion of the pipe being heated. A heater that utilizes hot exhaust gasses from an internal combustion engine or other source is disclosed in Temple's U.S. Pat. No. 4,437,453. It has an internal fixed perforated diffuser that is not readily adaptable to alternate heat sources. The perforated diffuser remains in direct contact with the workpiece at all times during the heating process which provides uneven heat transfer. Because the diffuser supports the workpiece, it is more difficult to visually determine if the workpiece has become pliable.